bb BIMBuilding Information Modelling, or BIM, is a smart choice for recording different information about a building; and is increasingly being adopted in building projects in many parts of the world. The level of success achieved by adopting BIM is affected by many factors. The nature of the procurement arrangement used is one of the critical factors affecting the success of BIM adoption.


Procurement arrangements that are being used in the construction industry can be divided into four main groups as “Separated”, “Integrated”, “Management Oriented” and “Collaborative”. Under each of the above group, there are several procurement arrangements. Each arrangement is developed in a particular way to fulfil a particular set of requirements. Some of these requirements are the design strategy, procurement of project participants, depth of client’s involvement for technical and procurement aspects, and the technology used. As an example, a Lump-Sum arrangement is for a fixed contract sum where design is finalised while Measure-and-Pay arrangement is simply, for fixed rates where design is not finalised. Both these are Separated procurement arrangements.

BIM is a technological framework which is developed to achieve project success through design accuracy. 99% design accuracy can be obtained through BIM, which in turn would lead to an unprecedented ‘no variation’ situation and the highest potential to produce a building which is ‘factory made’ and assembled on site. Nevertheless, to achieve such a goal, BIM should be combined with a suitable procurement arrangement.

The perfect procurement arrangement for BIM can be identified as the “COLLABORATIVE” procurement arrangement. To understand ‘why’ collaboration is needed, first we need to understand the general method that is practiced in the industry.

In all most all the other arrangements designing is done by a single party, generally being a consultant to the client. Contractor comes in to play once the design is developed up to a certain level. Generally the contractor is not being involved for the design stage where there is no contribution of the contractor’s knowledge of construction to the designing stage. Furthermore, the design consultants also work in isolation with less communication. The Architect develops the design and then the structural and services engineers input their parts for the design. This leads to clashes between design components and design incompatibilities. Incompatibilities occurred during design (due to less communication) are generally identified during construction, where they are solved as variations resulting cost and time overruns of the project. Another important factor we normally face in local industry is that, issuing of detailed drawings during construction. In the industry context that these issues continued to be significant, BIM is developed to overcome them through ‘collaborative working’ and ‘smarter information sharing’.

For BIM to be successful the designing process should be done as a collective endeavour of all the key parties. BIM platform is developed for the purpose of making a single, 100% detailed, multi-parameter model. All the design consultants and other key parties develop the same design together where incompatibilities and design clashes are identified easily. This requires the parties to work in the same work environment from the beginning by using the same set of software (leads to no technical difficulty later on) by using technologies such as cloud computing. Alternatively, parties may chose to use openBIM standards (IFC) as the central BIM and use openBIM compatible software of their choice. However, if this method suits to an early adopter of BIM is not yet clear.

Involving the contractor from the beginning helps the designers to use the contractor’s technical knowledge to increase the buildability of the project. This obviously leads to fewer troubles during construction. Client can view the design throughout the designing stage where he can look at the exact 3D model of his final product. If client wants a change, it can be easily achieved during designing stage leading to a no variation situation during construction.

For the above things to be achieved, the parties need to work collaboratively with each other, from the beginning. Since the design is a collective effort, parties should remain to work collaboratively until the end of the project. Therefore design risk should not be assigned to one party, but should be shared as one group. Therefore collaborative procurement arrangements such as Partnering and Integrated Project Delivery (IPD) are ideal for BIM based project delivery.

Therefore unlike in other procurement arrangements, the parties to the contract should not be identified as individual parties who undertake a specific job, but as a temporary organization which is working in the same environment as one group towards a common goal.

by Anuradha Abeyratne